I practice Iyengar yoga. Yoga is a discipline. It is grounded in a set of teachings about the body and the mind. What this practice has to do with spirituality is, for me, an open question.

There is no question about one thing: to do yoga in America today is to make a statement. Doing yoga says that you are young and flexible, or maybe just that you are older and determined. You care about more than “just exercise.”

You, and more than 15 million other people, are in recovery from a steady diet of aerobics or running, or too much time spent with re-runs of Sex and the City. Even those who don’t do yoga will gesture vaguely toward the hope that they “should” do yoga, or “get back to” yoga. It is a .7 billion dollar industry, with more than 70,000 teachers. The old days of yoga practitioners wearing their tie-dyed T-shirts to the food co-op seem long gone.

I do Iyengar yoga. Not Ashtanga, or Bikram, or the oh-so-generic “Vinyasa” yoga. Naming your yoga is a statement of identity. It situates you as part of a yoga denomination, with a very particular set of doctrines about the way yoga should be practiced.

To do Iyengar is very different than joining into the “flow” of Vinyasa classes, where things go quickly, and sun salutations mix with twists and backbends. There, you might get some music to set the pace — a little Native American flute, perhaps a sitar-inflected hip hop mix, as the teacher tells you to “do what feels good to you.” I’ve even done Oms with Amy Winehouse moaning along. (I’ll admit, I kind of liked it.)

But none of that can be heard in the stolid silence of Iyengar classes. There you find no music, no dancing through a class with your individual flow. You don’t do what “feels good.” You do what is needed, as you launch into an entire class of backbends, or perhaps an hour and a half spent perfecting triangle pose.

As an avowed atheist, with only a tiny inclination toward sentimental humanism, I haven’t had much interest in the yoga sutras or the various books of wisdom that circulate in the yoga world. I’m dubious about collections of yoga poetry or daily meditations. (Although I do have a real fondness for the title of one of those “wisdom” books, which offers a fine bit of Buddhist wariness: After The Ecstasy, the Laundry.) When I challenge my body, quiet my mind, and pay attention to the state of things — this brings me a kind of joy. It is a different joy that what I feel when drinking wine with my friends, and different, too, than the joy of teaching a good class or holding a child’s hand. But a spiritual joy? I liked it when we called that poetry. Or happiness.

I do Iyengar yoga, and as such I am part of a long genealogy. Yoga is a spiritual tradition, thousands of years old, with a complex history intertwined with the development of Indian religious traditions. Americans were fascinated with their understandings of “Hindoo” practices from the mid-19th century onward. Emerson and Thoreau both eagerly read as much as they could about Hinduism. As one yoga history puts it, Thoreau’s A Week on the Concord and Merrimack Rivers “stacks quotes from the Bhagavad-Gita, like cordwood, and recommends it as highly as the Bible.”

Modern posture-based yoga, however, emerged alongside of the U.S. and European physical culture movement of the late 19th century, which associated moral health with physical health, including body-building and gymnastics. The YMCA was a global influence on the early development of this model of intense, individualized focus on athletic health for the masses. The YMCA was big in India, and it had a real influence on yoga’s modern development. In 1905 bodybuilder Eric Sandow traveled to India to promote physical culture; by that time, he was, according to Mark Singleton, “already a cultural hero.”

While Indians were embracing physical culture along the Western model, they were also embracing and reimagining yoga into a form of nationalist pride and anti-imperialist cultural production. As we might imagine, there were competing schools and approaches, but most shared the sense that India needed to re-energize its ancient traditions with a vital awakening of the (male) body.

At this point, several sages also began to export their own visions of the practice of yoga to the West. Some, like Vivekananda, taught breathing exercises along with philosophical lectures, while others introduced the few simple postures associated with hatha yoga in India.

It was only in the 1920s that Yogananda (Autobiography of a Yogi) introduced a version of yogic “muscle control,” which drew on the metaphysics of the American New Thought movement and the bodily postures of European bodybuilding as well as Hindu traditions. Yogananda told his followers that this practice offered “the highest possible degree of mental, physical, and spiritual well-being at the minimum expenditure of time and effort.” The Indian sage already understood the efficiency obsessions of his American audience.

I practice Iyengar yoga. The Iyengar style of yoga comes from the teaching of B. K. S. Iyengar, one of the most influential yogis in the world. He died in 2014 at the age of 95, and he was already an extraordinary practitioner in the 1930s. Here is a 1938 practice video:

His innovation was to slow down the yoga practice, and to demand the most profound and particular attention to detail.

Iyengar-style teachers will teach the poses deliberately, slowly. As an advanced student, when I go to class, I know I will be asked to hold the pose for a long time while carefully attending to alignment: the hands perfectly spaced, the pelvis balanced, the “three points” of the feet positioned evenly on the earth. The teacher may well explain the exact angle for the correct positioning of the foot in a standing pose or how to do camel pose by curling your upper back, right at T4 (for the initiated, that’s the 4th thoracic vertebrae).

These perfected bodily alignments are not achieved easily, however, and Iyengar yoga is known for its students’ enthusiastic embrace of an impressive array of props. There are blocks that extend the reach, and belts to tighten splaying body parts, and blankets and blocks and metal folding chairs, even ropes hanging from hooks in the walls. All of this can make the average Iyengar studio appear vaguely like a set-up for an S&M session, albeit with big windows and cheery lights.

B. K. S. Iyengar was still a boy when modern hatha yoga began to become popular in India. He was a student of Krishnamacharya, the famous founder of the “Mysore school” that taught a vigorous form of yoga to young Brahmins. Iyengar eventually went to teach in Pune, a provincial capital in Western India, quite distant from the elite and insulated culture of the Mysore Palace. In Pune he taught students who were far removed from the young, flexible boys who had been the core of the Mysore tradition under Krishnamacharya. Working with non-adepts, Iyengar eventually started to slow down the practice, and to use the props for which he became famous.

From here, there is a longer story that could be told about the embrace of yoga in the West, and the development of competing systems like that of Iyengar and Pattabhi Jois, the founder of Ashtanga yoga. (He and Iyengar soon became global stars and serious rivals.) Iyengar was a much admired yoga teacher in India in the 1940s, but he became the exemplar of modern yoga for the West when he published Light on Yoga in 1966. That book quickly became the standard reference, bringing yoga to a new generation of Americans and Europeans.

In 2004, Time declared Iyengar to be one of the most influential people in the world. The full and rather remarkable history of Iyengar’s life and his global influence cannot be adequately recounted here. It is told elsewhere, including in Iyengar’s autobiography Iyengar: His Life and Work.

I practice Iyengar yoga. Just as surely as it says something about what happens when I walk into class, this statement locates me firmly in the social order of the yoga world. In that world, the Ashtanga yogis are the track stars and the class presidents. They glide through conferences, with shoulders sculpted by sun salutations, looking lithe and confident.

The Bikram folks are purified by their steamy practice rooms. I’m pretty sure the phrase “hot yoga” wasn’t meant as a pun, but it’s hard to avoid the association: these yogis look good, and they wear excellent, color-coordinated spandex. The Anusara yogis are lovely, emotionally open souls who are destined to run the bake sales that raise money for children’s charities. The Iyengar folks like to think of ourselves as more intellectual and precise. For everybody else, we’re more like the kids who stay home on Saturday night, carefully searching for flaws in the design of Klingon war ships.

For me, yoga in the West began when I showed up at Patricia Walden’s studio in Somerville, Massachusetts, in the mid-1980s. Walden was not yet the yoga superstar she would become when she made Yoga Journal’s “Yoga for Beginners” blockbuster videos. She was, however, an amazing teacher, and I knew it. Nonetheless, I developed slowly as a yoga student.

It was a hit or miss relationship for a long while. I would go to a class, try to do some yoga at home, watch Patricia’s tapes once in a while. I liked yoga — liked it well before Madonna or Gwyneth or Sting. But I was busy living my 20s and then my 30s, and consistency wasn’t my strong point: who had time?

Eventually, and for many reasons, I developed into a serious student with a daily yoga practice. I began to pay attention to the things that happened on the mat: how my body worked in this pose or that. When my mind wandered. When I gave up, and why. I struggled with poses — particularly with my bête noire, backbends. And I struggled, too, to figure out how I was supposed to get better at backbends if I was somehow also supposed to be “non-attached.” And, finally, in the middle of all that attention and struggle, I found my teacher.

I do Iyengar yoga and my teacher is John Schumacher. To name and claim one’s teachers is a common practice among serious yogis, a sign of respect. As a professor, I’m very impressed by this. For me, claiming John is also a statement about commitment; I’ve spent ten years in his classes, and I’m not going anywhere. John, however, is not my guru. He doesn’t do guru. And that’s one reason he’s remained my teacher; I don’t do guru either. What I do is listen and learn. And practice. And practice some more. And again the next day.

John is a particular kind of teacher, one who says relatively little about yoga philosophy directly, channeling pretty much everything through the poses themselves. Funny, sardonic, a little bit reserved, he is brilliant at structuring a class sequence. He demands attentiveness, and he offers attentiveness in turn. He also offers correction and advice, helping all of us avoid injury and commit to our practice.

In the remarkably demanding hours I spend in his class, I learn a great deal, but my emotional state is usually a strange combination of fearless jubilance and despair of my own inadequacy. (Iyengar himself is famously a hard ass; don’t let his winsome smile fool you.) John is a generous presence but a hard teacher. He is not a warm and fuzzy cheerleader for my empowerment. He does not begin class by reading a yoga sutra or end it by reading a poem. I am deeply grateful all of these things.

See, I don’t want to be part of a yoga world of happy talk about unending potential and perfect happiness. I don’t have much time for the kind of self-impressed platitudes that give yoga a bad name. Like so many of the secular, health-oriented, somewhat prideful members of my clan, I do yoga to quiet my brain, not to fill it with nonsense.

And yet nonsense abounds. Several years ago, I dropped in on a class at another studio. As class began, the teacher offered her thoughts about the goodness of the world and its benevolence toward us. “If you just reach out with your intention,” she said sagely, “the universe will rise to meet you half-way.” I almost walked out. The earthquake in Japan had happened the day before.

John also took the time to offer some thoughts. There is generally an opportunity at the beginning of class for us to ask questions, but these mostly involve things like where to put your elbow in a seated twist. This time, someone asked a question about the meaning of a yoga sutra. The sutra (II:3) states that “clinging to life” is an obstacle, “a pain-bearing obstruction.” In response, John said that “clinging to life” does not refer to what we do when we fight off an attacker or get surgery for cancer. Instead, clinging is the refusal to accept the reality of our own deaths, not just intellectually or abstractly, but fully and profoundly. To avoid clinging is to avoid the mistakes we make, both quotidian and profound, when we live without a recognition — an embrace — of our own mortality.

If this sounds like the yoga version of The Bucket List (or, worse, Tim McGraw’s maudlin country hit, “Live Like you were Dying”), it wasn’t. The point is that the practice of attentiveness — the fundamental practice that yoga cultivates — should lead us to contemplate the full reality of our life, which includes its inevitable end. As the yogi Richard Freeman puts it:

“Yoga is a rehearsal for death.”

That is the universe rising up to meet you.

For me, this discussion was a rare moment when I had some inclination of what “yoga spirituality” might mean, particularly for someone who doesn’t actually believe in spirituality. In this version, there is no promise of health or happiness. There is only our embrace of reality, in both its quiet joys and its suffering. We recognize ourselves as part of the universe, and we accept that universe’s fundamental indifference to us. Then we see what flows from that.

I suspect that this embrace of death, and life, doesn’t arise from an act of will or from reading the right books. Maybe, though, it comes from the act of the placing one’s feet in exactly the right alignment, and paying attention.

This essay was originally published on the SSRC Frequencies blog and is reprinted with permission under a Creative Commons License.